Cell migration induced by Leishmania (Leishmania) amazonensis, Leishmania (Leishmania) major and Leishmania (Viannia) braziliensis into the peritoneal cavity of BALB/c mice

Abstract

In American cutaneous leishmaniasis, the initial infection phase is characterized by recruitment of neutrophils and monocytes. The migration of these cells in response to the presence of Leishmania in the peritoneum of affected animals remains unclear. The objective of this study was to investigate cell migration to the peritoneum of BALB/c mice after infection with Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis and Leishmania (Leishmania) major. Initially, Leishmania spp. was intraperitoneally inoculated in five groups of six animals each and the cell migration was analyzed 0, 3, 6, 12, 24 and 48 hours after infection. Different cell counts were performed with a staining kit and showed a higher percentage of polymorphonuclear than mononuclear cells in all three species studied. The total cell count revealed peak migration in L. (L.) amazonensis and L. (L.) major at six hours, and in L. (V.) braziliensis at 12 hours. These results suggest that factors released from different cell types probably act by attracting polymorphonuclear cells, with the peak migration most likely depending on the species of Leishmania inoculated into the host

Leukocyte Behavior in Mesenteric Microcirculation upon Exper-imental By Leishmania Spp. in BALB/c Mice

“…In contrast, in peripheral blood, there was no difference with reference values, with predominance of mononuclear cells. However, Wakimoto et al ( 19 ) observed a predominance of polymorphonuclear cells in peritoneal exudate. The first cells migrating to the infection site can influence subsequent events such as cellular differentiation and targeting of the immune response towards one of two types: Th1, consisting of a strong cellular response that leads to cure, or Th2, with a low cellular response resulting in uncontrolled parasite proliferation and cutaneous lesions at the site of inoculation ( 17 ).…”

“…The initial events of Leishmania infections have been investigated using experiments involving mice ( 16 , 17 ). Although the skin is Leishmania ’s site of infection, the in vivo in situ study of cell recruitment into the cutaneous blood vessels of experimental animals presents certain limitations ( 18 , 19 ). In contrast, cellular recruitment in the peritoneal cavity of mice may reflect the initial stages of cellular migration upon Leishmania infection ( 19 ).…”

“…In the present study, there was an increase in the number of rolling leucocytes upon infection differed among the different Leishmania species. Studies have shown that in experimental Leishmania infections, cellular migration occurs in the skin after intradermal inoculation ( 12 , 20 ), in the peritoneum after intraperitoneal inoculation ( 19 ), and in the lymphoid organs ( 11 , 12 ). Matte and Olivier ( 11 ) reported that L. (L.) donovani and L. (L.) major induce the recruitment of different quantities of cells to the infection site.…”

“…The events that define the course of the Leishmania infection occur in the first hours or days after parasite inoculation. Wakimoto et al ( 19 ) reported cellular migration studies in peritoneal exudates after intraperitoneal infection, in which peaks occurred after 12 h for L. (V.) braziliensis and after 6 h for L. (L.) amazonensis and L. (L.) major . Under similar conditions, Matte and Olivier ( 11 ) also observed a peak after 6 h for L. (L.) major .…”

“…In resistant mice, PMN depletion induced by the injection of neutrophil and eosinophil inhibitors at the time of infection or during the first week of infection led to a significant increase in the parasitic load. In contrast, in susceptible animals, PMNs constitute the primary cellular population recruited within the first ten days following parasite inoculation ( 15 , 18 , 19 , 30 ).…”